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[IDV #IFH-755538]: T-REX BAe real-time data

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  • Subject: [IDV #IFH-755538]: T-REX BAe real-time data
  • Date: Tue, 10 Jul 2007 18:03:10 -0600
Hi all,

The FAAM file reads in as a trajectory/track dataset just fine. The BAe file, 
on the other hand, does not get recognized as a trajectory/track dataset. The 
problem is that it doesn't follow any of the conventions we recognize for 
defining which variables are the coordinate variables (latitude, longitude, 
elevation, and time).

I tried to write an NcML wrapper to add/modify a few attributes so that one of 
the existing convention readers would recognize it. It didn't work because the 
lat, lon, and alt variables are two dimensional arrays with the second 
dimension having a size of 1. None of our trajectory convention readers know 
how to deal with 2-D lat, lon, and alt variables.

Can you re-write any of this data to fit an existing convention?

Here's the NcML I tried:

<?xml version="1.0" encoding="UTF-8"?>
<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2"; 
location="R:/testdata/trajectory/aircraft/bae.nc">
  <attribute name="Conventions" value="NCAR-RAF/nimbus" />
  <attribute name="Version" value="1.3" />
  <attribute name="coordinates" value="PARA0581 PARA0580 PARA0582 Time" />
  <dimension name="Time" orgName="data_point" />
  <variable name="PARA0580" shape="Time" /> <!-- latitude variable -->
  <variable name="PARA0581" shape="Time" /> <!-- longitude variable -->
  <variable name="PARA0582" shape="Time" /> <!-- altitude variable -->
</netcdf>

The three <variable> elements were my attempt to reduce the dimensionality of 
the lat, lon, alt variables. But the netCDF-java code doesn't actually know how 
to do this correctly (I guess this wasn't a target use case when the NcML code 
was written).

Ethan


Ticket Details
===================
Ticket ID: IFH-755538
Department: Support netCDF Java
Priority: Normal
Status: Open